I would agree with the love / hate part.
However against his point, dealers are not interested in supporting a web platform of any kind. They pay groups (like the ones we've listed so many times) to maintain it for them. Dealers sell cars; web development groups sell websites; agencies do marketing. Templates should be set up to allow for manipulation by dealers (internal people), but not to build on it per se. That's been the case for some time.
I do believe it depends on how deeply developed a theme is though. There are bells and whistles (plugins packaged) that allow for much greater forms of editing. Now, do the automotive web hosting companies utilizing WP allow for such detail, that's on them.
https://www.drivingsales.com/forums/marketing/wordpressbased-website-providers
Dealer Inspire - http://www.dealerinspire.com/
Dealer X - http://www.dealerx.com/
AutoRevo - http://www.autorevo.com/
We Are Full Throttle (Stream) - https://www.wearefullthrottle.com/
Steering Innovation - http://www.steeringinnovation.com/
Fox Dealer - http://www.foxdealer.com/
eDealer - http://www.edealer.ca/
DealerTrend - http://www.dealertrend.com & http://cardealerpress.com/
I'd say that many of those groups are successful.
